And it could be the world’s largest. A team of scientists, led by Durham University, spotted the massive canyon system in one of the last unexplored regions on Earth. Princess Elizabeth Land (PEL) in East Antarctica. PEL is known as one of Antarctica’s two ‘Poles of Ignorance.’ Even ice thickness measurements are few and far between in this area.
“This is a region of the Earth that is bigger than the UK and yet we still know little about what lies beneath the ice. In fact, the bed of Antarctica is less well known than the surface of Mars. If we can gain better knowledge of the buried landscape we will be better equipped to understand how the ice sheet responds to changes in climate.”
Analysis of satellite data points to a canyon that is believed to be over 1,000 kilometers long and as deep as 1 kilometer in spots. How does that stack up against some of the world’s largest canyons? The Grand Canyon in Arizona stretches 446 kilometers and is over a mile deep at its deepest point.
Here’s a satellite image of the Princess Elizabeth Land region.
And here’s another image with the canyons and possible subglacial lake mapped out.
Scientists don’t know exactly how big the canyon is, and will need direct measurements to confirm their discovery.
How do you spot a canyon beneath the ice sheet?
Satellite imagery highlighted faint traces of the huge canyon. Scientists then used radio-echo sounding data to locate small sections. Radio waves were sent through the ice to figure out the shape of the rock beneath it. Once they analyzed the data, scientists realized they were looking at a gigantic canyon beneath the East Antarctic ice sheet.
How did the canyon form? Water is the likely answer according to scientists. But the age of the canyon is up in the air. Was it already there before the ice sheet grew? Or, was it formed from flowing water beneath the ice sheet? Scientists hope to get a better handle on its age in the current survey.
Right now, an airborne survey is underway. Using targeted radio-echo sounding measurements, scientists hope to confirm the exact measurements of the canyon later this year.
Co-author Professor Martin Siegert (Grantham Institute at Imperial College London) thanked the many organizations that made the discovery possible.
“Our identification of this landscape has only been possible through the recent acquisition, compilation and open availability of satellite data by many different organisations (e.g. NASA, ESA and the US National Snow and Ice Data Center), to whom we are very grateful, and because of some serendipitous reconnaissance radio-echo sounding data acquired over the canyons by the ICECAP project during past Antarctic field seasons.”
A possible lake?
Scientists also believe the canyon system may be connected to a previously undiscovered subglacial lake. The ice surface above the possible lake shares similar features with large subglacial lakes discovered before. The data suggests a lake covering an area up to 1250km².
“Our analysis provides the first evidence that a huge canyon and a possible lake are present beneath the ice in Princess Elizabeth Land. It’s astonishing to think that such large features could have avoided detection for so long,” says Jamieson.
Image credits: Durham University / Dr. Stewart Jamieson